Polishing Quartz and Beryl
Jeff R Graham share about polishing quartz and beryl in Just Ask Jeff. See what his answers are to How to Polish Quartz & Beryl?
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Polishing Quartz and Beryl
The most important thing about polishing Quartz and Beryl is to have a very good pre-polish on the stone before you attempt to polish.
Rough cut your stone like you normally would. I use a well worn Crystalite steel 260 grit lap, unless the stone is large. If it is a large stone I often rough it in with a Crystalite steel 100x grit lap then cut with the worn 260.
Next I use a worn 600 lap for meeting the tier/facets, this lap will still cut, but not fast, making it easy to control and leaving a nice scratch free finish. It is important to have all the facets at meet point and well cut before going to the 1200 Nu Bond, because it is basically a pre-polish lap and will not cut much.
Note: A 3,000 grit diamond lap works well also, instead of the 1200 Nu Bond. There is the option of charging a 3,000 lap your seld, using a tin lap or a phenolic lap.
I have tried several combinations, but I think that the RayTech composite 1200 (Nu Bond) lap, especially after it is broken in a little, is ideal for a quality pre-polish on Beryl, and Quartz. A Crystalite 3,000 can work well also and is a little flatter, but I prefer the finish of the RayTech.
The RayTech Nu bond 1200 will hardly cut at all (when it is broken in) and is not the flattest lap I have ever used, but it leaves a great finish that with just a touch on the polish lap will make a high polish. I really do not use the Nu Bond 1200 for anything else but Quartz, and Beryl. The 1200 Nu Bond is too fine for Tourmaline and Garnet. It will leave an orange peel finish that is hard to polish through on these material.
For polish I prefer the Spectra Ultra Laps, they are a mylar film that is coated with a high grade polish, on the dull side. Some people claim that Ultralaps round the facets, but I have found that with a little practice and a light touch they work as well as anything I have ever found and are fairly cheap to use. Recharging Ultralaps with a Cerium Oxide (CeO2) slurry extends them quite a bit. What is a Spectra (Ultralap) Lap? How do I use them?
I use my Nu bond 1200 lap for a base (it is the last cutting lap on the stone so there is not cheating needed) with a little bit of water on it to make a seal between the Spectra Ultralap and it, and with a moderate lap speed, it only takes a second to polish a facet.
Other polishing laps for Quartz are:
A plastic lap with CeO2 (cerium oxide).
A tin lap scored with CeO2, this works well, but needs to be a dedicated lap and is more money.
A phenolic lap with CeO2. This works very well and is probably my favorite. But keep in mind a phenolic lap will take a fair amount of time to break in and become "charged" with CeO2, before it really works fast.
Jeff R. Graham
The late Jeff Graham was a prolific faceter, creator of many original faceting designs, and the author of several highly-regarded instructional faceting books such as Gram Faceting Designs.
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